The application generally relates to a rotational gravitational gradiometer. The application relates more specifically to a quadrupole responder for an Orthogonal Quadrupole Responder (OQR)-type gravity gradiometer.
A gravity gradiometer measures a gravitational field. Gravity gradiometers can be used, e.g., for controlling and stabilizing the attitude of an artificial earth satellite. The gravity gradiometer may include a gravity gradient member mounted in a gimbal arrangement to have two degrees of freedom. In other gravity gradiometers a flexural pivot and torsion spring may be required.
A gravity gradiometer may measure the Riemann curvature of spacetime produced by nearby masses. By flying a gradiometer in an airplane above the Earth's surface, one can measure subsurface mass variations due to varying geological structure. In an Earth-orbiting satellite, such a gradiometer could measure the gravitational multi-pole moments of the Earth.